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  1. 18 8月, 2006 1 次提交
    • M
      [BNX2]: Fix tx race condition. · 2f8af120
      由 Michael Chan 提交于 
      Fix a subtle race condition between bnx2_start_xmit() and bnx2_tx_int()
similar to the one in tg3 discovered by Herbert Xu:

CPU0					CPU1
bnx2_start_xmit()
	if (tx_ring_full) {
		tx_lock
					bnx2_tx()
						if (!netif_queue_stopped)
		netif_stop_queue()
		if (!tx_ring_full)
						update_tx_ring
			netif_wake_queue()
		tx_unlock
	}

Even though tx_ring is updated before the if statement in bnx2_tx_int() in
program order, it can be re-ordered by the CPU as shown above.  This
scenario can cause the tx queue to be stopped forever if bnx2_tx_int() has
just freed up the entire tx_ring.  The possibility of this happening
should be very rare though.

The following changes are made, very much identical to the tg3 fix:

1. Add memory barrier to fix the above race condition.

2. Eliminate the private tx_lock altogether and rely solely on
netif_tx_lock.  This eliminates one spinlock in bnx2_start_xmit()
when the ring is full.

3. Because of 2, use netif_tx_lock in bnx2_tx_int() before calling
netif_wake_queue().

4. Add memory barrier to bnx2_tx_avail().

5. Add bp->tx_wake_thresh which is set to half the tx ring size.

6. Check for the full wake queue condition before getting
netif_tx_lock in tg3_tx().  This reduces the number of unnecessary
spinlocks when the tx ring is full in a steady-state condition.
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2f8af120
  3. 09 8月, 2006 1 次提交
  5. 08 8月, 2006 2 次提交
    • M
      [TG3]: Fix tx race condition · 1b2a7205
      由 Michael Chan 提交于 
      Fix a subtle race condition between tg3_start_xmit() and tg3_tx()
discovered by Herbert Xu <herbert@gondor.apana.org.au>:

CPU0					CPU1
tg3_start_xmit()
	if (tx_ring_full) {
		tx_lock
					tg3_tx()
						if (!netif_queue_stopped)
		netif_stop_queue()
		if (!tx_ring_full)
						update_tx_ring 
			netif_wake_queue()
		tx_unlock
	}

Even though tx_ring is updated before the if statement in tg3_tx() in
program order, it can be re-ordered by the CPU as shown above.  This
scenario can cause the tx queue to be stopped forever if tg3_tx() has
just freed up the entire tx_ring.  The possibility of this happening
should be very rare though.

The following changes are made:

1. Add memory barrier to fix the above race condition.

2. Eliminate the private tx_lock altogether and rely solely on
netif_tx_lock.  This eliminates one spinlock in tg3_start_xmit()
when the ring is full.

3. Because of 2, use netif_tx_lock in tg3_tx() before calling
netif_wake_queue().

4. Change TX_BUFFS_AVAIL to an inline function with a memory barrier.
Herbert and David suggested using the memory barrier instead of
volatile.

5. Check for the full wake queue condition before getting
netif_tx_lock in tg3_tx().  This reduces the number of unnecessary
spinlocks when the tx ring is full in a steady-state condition.

6. Update version to 3.65.
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1b2a7205
    • C
      [TG3]: skb->dev assignment is done by netdev_alloc_skb · d14cc9a3
      由 Christoph Hellwig 提交于 
      All caller of netdev_alloc_skb need to assign skb->dev shortly
afterwards.  Move it into common code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d14cc9a3
  7. 04 8月, 2006 5 次提交
  9. 03 8月, 2006 9 次提交
  11. 29 7月, 2006 2 次提交
  13. 28 7月, 2006 5 次提交
  15. 26 7月, 2006 3 次提交
  17. 22 7月, 2006 5 次提交
  19. 21 7月, 2006 1 次提交
  21. 18 7月, 2006 3 次提交
  23. 15 7月, 2006 3 次提交